. Mississippi

Small businesses have long been a cornerstone of Mississippi's economy, since few large corporate headquarters or R&D facilities are based here. Indeed, many new college grads choose to start their careers by launching a business, said Tony Jeff, CEO of Innovate Mississippi, a nonprofit that helps early-stage companies.

Startups can get help doing research and finding capital through Mississippi State University's Entrepreneurship Center. They also can enroll in business-training bootcamps offered throughout the state by the Mississippi Development Authority.

Source: 2013 Kauffman Index of Entrepreneurial Activity, published by the Kauffman Foundation. The 2012 startup rate for each state is based on a yearly national survey of about half a million people -- adults aged 20 to 64 who start a business each month with 15 or more hours worked. In Montana, for example, Kauffman found that 530 of every 100,000 adults started businesses in 2012.